CN101267439B - Generation method, node communication method, device and system for medium access control protocol - Google Patents

Abstract

The invention discloses a method for generating a medium access control (MAC) protocol, which includes: a preprocessing step: determining a basic access mechanism; setting multiple expansion functions according to user requirements, and setting and selecting configurable parameters for each expansion function; Generation step: when the user configures the configurable parameters according to the target MAC protocol, determine the extension function corresponding to the configurable parameter whose content is preset data; perform code loading and compiling on the selected extension function together with the basic access mechanism , generating the target MAC protocol. The invention also discloses a device for realizing the above method, a communication method between nodes and a wireless multi-hop network. The embodiment of the present invention solves the problem that the prior art does not have universality and compatibility due to the tight coupling of protocols and user requirements.

Description

Medium access control protocol generation method, node communication method, device and system

technical field

The present invention relates to the field of wireless network technology, and more specifically, to a method and device for generating a MAC (Media Access Control) protocol in a wireless multi-hop network, and a method and device for node communication based on the method for generating the protocol.

Background technique

In the wireless network, there is a wireless multi-hop network, and the wireless multi-hop network can be an ad hoc network or a sensor network.

Let’s take the sensor network as an example to illustrate:

The sensor network is composed of a large number of tiny sensor nodes integrating wireless communication, information collection and information processing functions. Each sensor node uses its own sensor to collect the information of the surrounding environment, and then transmits the information to the data aggregation node (also called the Sink node) in the network. Since there are many nodes in the network, the coverage is large, and wireless communication is adopted, when multiple nodes need to communicate, it is necessary to establish certain criteria to determine which nodes can communicate and which nodes cannot communicate, so as to avoid conflicts And the waste of channel resources, this is the core problem to be solved by the MAC protocol.

Existing MAC protocol designs are all carried out from the perspective of user requirements. Here, the "user requirements" refer to different requirements of users for information collection in the network. In the sensor network, the needs of users are various, such as: pay attention to the energy consumption of information transmission, pay attention to the delay of information transmission, pay attention to the reliability of information transmission, and so on. This design concept makes the designed protocol tightly coupled with user needs. This makes the MAC protocols in different sensor networks very different. At present, a MAC protocol can only be realized based on one access method, it is difficult to support a variety of different applications, and there is no compatibility, which makes the products supporting this protocol not universal, for example: for coal mine underground For the needs of safe positioning and environmental monitoring of the Yellow River wetland, the existing technology usually designs two different MAC protocols and products supporting these two different protocols, which wastes resources.

Contents of the invention

In view of this, the embodiments of the present invention provide a method for generating a medium access control protocol, a node communication method and an apparatus, so as to solve the problem of incompatibility in the prior art due to the tight coupling between protocols and user requirements.

The embodiment of the present invention is realized like this:

A method for generating a media access control MAC protocol, comprising:

Preprocessing steps:

Identify basic access mechanisms;

Set the extension functions of multiple configurable mechanisms according to user needs, and set configurable parameters for the extension functions of each configurable mechanism;

Build steps:

When the user configures the configurable parameters according to the target MAC protocol, determine the extension function of the configurable mechanism corresponding to the configurable parameters whose content is preset data;

Perform code loading and compiling on the selected extended function together with the basic access mechanism to generate the target MAC protocol.

Preferably, the basic access mechanism is a p-persistent CSMA protocol.

Preferably, the extended function is: resource reservation function, interception function, handshake function, backoff function, confirmation function, transmission probability control function or synchronization management function.

The present invention also discloses a node communication method, which is applied to a wireless multi-hop network, including:

Preprocessing steps:

Identify basic access mechanisms;

Set the extension functions of multiple configurable mechanisms according to user needs, and set configurable parameters for the extension functions of each configurable mechanism;

Build steps:

The sending node determines the MAC protocol of the receiving node before sending data to the receiving node, and when the user configures the configurable parameters according to the MAC protocol, determines the extended function corresponding to the configurable parameter whose content is equal to the preset data;

The sending node loads and compiles the selected extended function together with the basic access mechanism to generate the MAC protocol;

Communication steps:

The sending node and the receiving node communicate using the MAC protocol as a communication protocol.

Preferably, in the above method, the specific manner for the sending node to determine the MAC protocol of the receiving node is:

The sending node records the protocol version number information of the receiving node through idle listening, and the version number information includes the configurable parameter content corresponding to each extended function;

The sending node determines the MAC protocol of the receiving node according to the content of the configurable parameter.

Preferably, in the above method, the basic access mechanism is the CSMA protocol adhered to by p, and the extended function is: resource reservation function, listening function, handshake function, backoff function, confirmation function, transmission probability control function or synchronization management functions.

The invention also discloses another node communication method, which is applied to a wireless multi-hop network, including: preprocessing steps:

Identify basic access mechanisms;

Set the extension functions of multiple configurable mechanisms according to user needs, and set configurable parameters for the extension functions of each configurable mechanism;

Build steps:

The receiving node determines the MAC protocol of the sending node, and when the user configures the configurable parameters according to the MAC protocol, determines the extended function corresponding to the configurable parameter whose content is equal to the preset data;

The receiving node loads and compiles the selected extended function together with the basic access mechanism to generate the MAC protocol;

Communication steps:

The sending node and the receiving node communicate using the MAC protocol as a communication protocol.

Preferably, in the above method, the specific manner for the receiving node to determine the MAC protocol of the sending node is:

The receiving node records the protocol version number information of the sending node through idle listening, and the version number information includes the configurable parameter content corresponding to each extended function;

The receiving node determines the MAC protocol of the sending node according to the content of the configurable parameter.

Preferably, in the above method, the basic access mechanism is the CSMA protocol adhered to by p, and the extended function is: resource reservation function, listening function, handshake function, backoff function, confirmation function, transmission probability control function or synchronization management functions.

The invention also discloses a medium access control MAC protocol generation device, including:

The first storage unit is used to store the basic access mechanism identifier and the corresponding code;

The second storage unit is used to store the extended function identifiers and corresponding codes of various configurable mechanisms, and configuration parameters corresponding to the extended functions of each configurable mechanism;

The first processing unit is configured to determine the extended function identifier corresponding to the configurable parameter whose content is equal to the preset data when the user configures the configurable parameter according to the target MAC protocol;

The second processing unit is configured to load and compile the code corresponding to the selected extended function identifier together with the code of the basic access mechanism to generate the target MAC protocol.

Preferably, in the above device, the basic access mechanism is the CSMA protocol adhered to by p, and the extended functions are: resource reservation function, interception function, handshake function, backoff function, confirmation function, transmission probability control function or synchronization management function .

The present invention also discloses a wireless multi-hop network, which includes several nodes, the nodes include a communication unit, and the nodes also include a medium access control MAC protocol generation device and a MAC protocol determination unit;

The MAC determining unit is used to determine the MAC protocol of the target node before the communication unit communicates with the target node, and the device includes:

The first storage unit is used to store the basic access mechanism identifier and the corresponding code;

The second storage unit is used to store the extended function identifiers and corresponding codes of various configurable mechanisms, and the configurable parameters corresponding to the extended functions of each configurable mechanism;

The first processing unit is configured to determine the extended function identifier corresponding to the configurable parameter whose content is preset data when the user configures the configurable parameter according to the MAC protocol of the target node;

The second processing unit is configured to load and compile the code corresponding to the selected extended function identifier together with the code of the basic access mechanism to generate the MAC protocol of the target node;

The communication unit sends data to the target node according to the generated MAC protocol, and receives the data

The data fed back by the target node.

Preferably, in the above network, the basic access mechanism is the CSMA protocol adhered to by p, and the extended functions are: resource reservation function, interception function, handshake function, backoff function, confirmation function, transmission probability control function or synchronization management function .

It can be seen from the above technical solutions that, compared with the prior art, the embodiment of the present invention uses an access mechanism as a basic access mechanism, and uses a preset configurable mechanism as an extended part. Select and configure the mechanism of the extension according to the user's needs, and combine it with the basic access mechanism to generate a corresponding protocol. Using the MAC protocol generation method disclosed in the embodiment of the present invention, the corresponding MAC protocol can be generated according to the needs to meet the various needs of the user, and realize the intercommunication between different access mechanisms: for example, some nodes in the network use the ALOHA protocol, Another part of nodes adopts CSMA (Carrier Sense Multiple Access) protocol, and then the two parts of nodes can realize communication through the solution disclosed in the present invention.

Description of drawings

FIG. 1 is a flowchart of an embodiment of a method for generating a media access control protocol according to the present invention;

FIG. 2 is a schematic structural diagram of a time slot in an embodiment of the present invention;

FIG. 3 is a flow chart of Embodiment 1 of a node communication method according to the present invention;

FIG. 4 is a flow chart of Embodiment 2 of a node communication method of the present invention;

Fig. 5 is a schematic diagram of a message format;

Fig. 6 is a schematic structural diagram of an embodiment of an apparatus for generating media access control according to the present invention.

Detailed ways

At present, there are various MAC protocols in wireless sensor networks, and there are more than 30 mainstream protocols. But in essence, it is all about the coordination and management of how multiple nodes in the network access the channel, nothing more than ALOHA-based MAC protocol, CSMA-based MAC protocol and TDMA (Time Division Multiple Access, Time Division Multiple Access) MAC protocol.

in:

ALOHA-based MAC protocols include: slotted/non-slotted ALOHA protocol, slotted/non-slotted ALOHA protocol sent with probability p, and slotted/non-slotted ALOHA protocol with acknowledgment, etc.

CSMA-based MAC protocols include: p-persistent slotted/non-slotted CSMA protocol, 1-persistent slotted/non-slotted CSMA protocol, slotted/non-slotted CSMA protocol with handshake mechanism, and slotted acknowledgment / Non-slotted CSMA protocol, etc.

The TDMA-based MAC protocol includes: a pre-allocated access mechanism implemented in a certain way.

Various protocols are designed for a specific requirement of the user, and cannot be used in common with each other. Thus, it is not possible to use different protocols in a network or to have a group of devices support different access mechanisms. Based on this, the present invention proposes a method for generating a MAC protocol, that is, an access mechanism is used as a basic access mechanism, and a preset configurable mechanism is used as an extended part. Select and configure the mechanism of the extension according to user needs, and combine it with the basic access mechanism to generate a corresponding protocol.

However, there is no relevant literature on the general MAC protocol at home and abroad. The MAC protocol of the wireless personal area network standard 802.15.4 (Zigbee) or the MAC protocol of 802.11, although there are changes in the message exchange process and specific procedures, is essentially a deformation based on CSMA and does not provide anything other than CSMA, such as ALOHA or TDMA access method.

In order to enable those skilled in the art to better understand the technical solutions of the embodiments of the present invention, the technical solutions of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

Please refer to FIG. 1 , which is a flowchart of an embodiment of a method for generating a media access control protocol according to the present invention.

Specifically include the following steps:

Step S100, a preprocessing step.

This preprocessing step includes the following steps:

Step S101, determining a basic access mechanism.

Among the existing ad hoc network and sensor network MAC protocols, there are more than 60 mainstream protocols and more than 100 derivative protocols. 90% of them are random competition type agreements. 85% are based on carrier sense and collision avoidance mechanisms. Explain that user needs are mainly based on this type of agreement.

Among the numerous MAC protocols, there are only three basic access methods: ALOHA protocol, CSMA protocol and TDMA protocol.

In principle, any one of the above three protocols can be used as a basic access mechanism, for example, ALOHA can be used as a basic access mechanism, and TDMA can also be used as a basic access mechanism. However, there are very few user groups for these access methods, and when ALOHA or TDMA is used as the basic access mechanism, its extended complexity is much greater than that of CSMA. The extended complexity refers to: generating The types and combination methods of extended functions that need to be defined by other specific protocols. This indicator reflects the complexity of the protocol generation and compilation process.

As shown in Fig. 2, it can be seen that the expansion complexity of adopting p-adherent CSMA protocol as the basic access mechanism is smaller than that of ALOHA and TDMA as the basic access mechanism.

Therefore, this paper determines that p adheres to the CSMA protocol as the basic access mechanism.

The specific content of the CSMA protocol insisted by p is as follows: the node performs carrier sense before sending data, if the channel is idle, then sends data with probability p, if the channel is busy, then continues to listen until the channel becomes idle, Then, send data with probability p.

Step S102, setting various extension functions according to user requirements.

The extended function is a function implemented according to various regulations of various MAC protocols, for example: interception function, handshake function, or synchronization management function.

Set configurable parameters for each extension.

The configurable parameter is used to indicate whether the corresponding extended function is selected, for example, if the data is 1, it means that the extended function is selected, and if it is 0, it means that the extended function is not selected.

Users can realize the selection of extended functions by controlling the switches of all the parameters.

The following introduces several extended functions and corresponding parameter switches:

①. Resource reservation function

In a network with time slots, the embodiments of the present invention support the use of channels in a reserved manner.

A certain time slot can be pre-allocated to a certain node. There are many ways to allocate time slots. For example, when laying out the network, pre-allocate part of the time slots for part or all of the power saving.

A reserved flag bit can be set in the time slot structure, as shown in FIG. 3 . It is a schematic diagram of the structure of the time slot in the embodiment of the present invention.

It can be seen from Figure 3 that each time slot is composed of several time units, and there is a reserved flag bit of an time unit at the head of each time slot. If the time slot is a reserved time slot of a node and the node If there is data to be sent, the node sends a busy tone signal in the reserved flag. If other non-TDMA nodes want to use the time slot, they first judge whether the flag is empty. If non-empty, this slot cannot be used.

This resource reservation function can ensure that the node that reserves resources has the highest access priority.

The content of the configuration parameter Resource obligate-flag: 1 means that TDMA is used (that is, the extended function is used); 0 means that the default setting is used (that is, the extended function is not used); 0XFF means that the manual setting is invalid, that is, the automatic Determines whether to select extensions.

②, listening function

The user can configure the configuration parameter CS-flag. If the content of the configuration parameter CS-flag is 1, it means that the interception function is used; That is the ALOHA mode; 0XFF means that the manual configuration is invalid, that is, the automatic selection listening mechanism is adopted, that is: according to the neighbor node list and the channel traffic statistics table maintained by the node, when the number of nodes and the traffic volume are small, no Use the listening mechanism instead of sending directly (ALOHA). If the traffic volume or the number of nodes is large, the carrier sense mechanism is adopted.

③. Handshake function:

The user can configure the configuration parameter Handshake-flag. If the content of the configuration parameter Handshake-flag is 1, it means that the handshake function is used; when it is 0, it means that the handshake function is not used (that is, pure CSMA); when it is 0XFF, it means manual configuration invalid. That is to say, it means to automatically choose whether to use the listening mechanism, that is, to judge the packet length, if the packet length is longer than a certain threshold value, the handshake mechanism is adopted; if the packet length is smaller than the threshold value, the handshake mechanism is not adopted.

The operation of the protocol takes precedence over manual configuration.

④, retreat function:

The user can configure the configuration parameter CWmin-fix. If the content of the configuration parameter CWmin-fix is 1, it means manually setting a fixed backoff window, which means that the user is allowed to configure the size of the backoff window; if it is 0, it means manually setting the minimum backoff window The initial value of the window (in units of epochs); when it is 0XFF, it means that the manual setting is invalid, that is, it means that the fixed backoff window is automatically set, and the backoff algorithm can use the BEB (Binary Exponential Backoff Algorithm) algorithm, or other backoff algorithms algorithm. For the BEB algorithm, the specific process of setting a fixed backoff window is: determine the number of neighbor nodes in the neighbor node list, and if the number of neighbor nodes in the neighbor node list is less than a certain threshold value, reduce the minimum value of the backoff window. Otherwise, increase the minimum value of the backoff window.

The operation of the protocol takes precedence over manual configuration.

⑤. Confirmation function:

The configuration parameters include the feedback flag ACK-flag and the feedback type ACK-type. When the content of ACK-flag is 1, it means the acknowledgment function is used, and which services use this function is explained by ACK-type; when it is 0, it means that the acknowledgment mechanism is not used, and those services that do not use it are explained by ACK-type; when it is 0XFF, it means manual The configuration is invalid, which means that the confirmation mechanism is automatically selected, that is, whether to use the confirmation mechanism is selected according to the business type. For the unicast service, the confirmation mechanism is adopted, and the confirmation mechanism is not adopted for the broadcast service. The distinction of different service types is realized through the address of the destination node.

ACK-type content: when it is 0X01, it means unicast; when it is 0X02, it means broadcast; when it is 0X03, it means multicast; when it is 0X00, it means all service types. It is used to indicate which type of packet adopts or does not adopt the confirmation mechanism. For example, when the ACK-flag is 1 and the ACK-type is 0X01, it indicates that the acknowledgment function is used for the unicast service.

The operation of the protocol takes precedence over manual configuration.

⑥Send probability control function:

The embodiment of the present invention allows the user to manually configure the sending probability, for example, the user can configure a fixed sending probability, so that nodes in the network use the same reference sending probability, or use a fixed sending probability. If the content of the configuration parameter p-flag is 1, it means that the initial value is manually configured; if it is 0, it means that the fixed sending probability is configured manually; if it is 0XFF, it means that the manual configuration is invalid, that is, the method of automatically selecting the sending probability is used, that is : The business volume statistics table maintained by the node. If the business volume exceeds a certain threshold, the sending probability will be reduced, otherwise the sending probability will be increased. In this way, each node in the network can dynamically adjust the sending probability according to its surrounding environment. The specific algorithm has been published as a public paper and can be cited if necessary.

The operation of the protocol takes precedence over manual configuration.

⑦. Synchronization management function:

The synchronization management part mainly completes the maintenance of the synchronization status of nodes. If it is an asynchronous network, this part does not need to run. If it is a synchronous network, this part completes the counting function of epochs and time slots.

The protocol defaults to the configuration of the asynchronous network. If you want to change the configuration, you need to configure the content of the configuration parameter Synchronization-flag. When the content is 1, it means a synchronous network, and if it is 0, it means an asynchronous network.

It should be noted that the above-listed extended functions are just some of the extended functions, and new extended functions can be determined according to the functions implemented according to the protocol.

In addition, it should be noted that, in the above-mentioned interception function, backoff function and transmission probability control function, the neighbor node list and the traffic statistics table can have different implementation methods, and the specific methods can be shown in Table 1:

Table 1

Node ID/business volume statistics Time slot 1 time slot 2 Slot 3 Node2 Occupy null Node3 conflict Occupy ...

This table is mainly used for the calculation of transmission probability and the setting of backoff window. In the ALOHA protocol, because there is no interception function, this table cannot be established, and the adaptive algorithm of transmission probability and backoff is also not supported.

After the preprocessing step is completed, the identifiers and codes of multiple extensions can be stored in a preset address, and then enter the generation step:

Step S200, a generating step.

The generation step consists of the following steps:

Step S201, acquiring the content of configurable parameters.

The user selects corresponding extended functions by setting configurable parameters according to the specific realization functions of the target MAC protocol.

During this process, the configurable parameter content is obtained.

Step S202, determining the extended function corresponding to the configurable parameter whose content is preset data.

According to the content of the configurable parameters, determine whether to use the corresponding extended function. For example, when the configurable parameter content of an extended function is 1, it means that the extended function is selected.

Step S203: Load and compile the determined extended functions and basic access mechanism to generate the target MAC protocol.

Obtain the corresponding code from the preset address according to the determined extended function identifier, load and compile the code together with the code of the basic access mechanism according to the content of the configurable parameters, and finally generate the target MAC protocol.

Here are a few specific examples to illustrate:

(1), assuming that the target MAC protocol is a TDMA protocol, the specific content of the TDMA protocol is:

Assume that each node is assigned a corresponding time slot according to the node ID number, that is, node 1 occupies time slot 1, and node 2 occupies time slot 2. but:

When a node has data to send, it sends a busy tone on the reserved flag of its own time slot. and send data at the beginning of the subsequent epoch.

If the amount of data of a node is large, if the reserved flag of a certain time slot is empty, data can be sent on this time slot, but this may cause data conflicts. In order to avoid conflicts, the probability of a node sending data is inversely proportional to the number of neighbor nodes of the node (it can also be manually configured as a fixed sending probability, which is determined by the sending probability control part.). The synchronization management unit is used here to count the time slots.

It can be seen that in the basic access mechanism, the required extended functions include: resource reservation function, interception function, handshake function, backoff function, confirmation function, transmission probability control function and synchronization management function.

By setting the content of the configuration parameters corresponding to the above-mentioned extended functions as preset data (for example: 1) to determine the selection of the above-mentioned extended functions, the user can configure the corresponding configuration parameters as follows:

Resource obligate-flag is set to 1, indicating that TDMA is used;

CS-flag is set to 0, and the carrier sense mechanism is not used;

Handshake-flag is set to 0, and the handshake mechanism is not used;

CWmin-fix is set to 1, indicating that the fixed backoff window is manually set, and CWmin is set to 0;

ACK-flag is set to 0, ACK-type is set to 0X00, indicating that all business types do not use the confirmation mechanism;

If p-flag is set to 0, it means that the fixed transmission probability is manually configured, and p is set to 1;

Synchronization-flag is set to 1, indicating that a synchronous network is used, and the number of nodes is set to N, and the synchronization management unit performs modulo N calculation on the count of time slots.

In addition, in order to avoid the occurrence of self-contradiction, a logic relationship check can be performed after the user configures the configuration parameters.

After the inspection is passed, the code for the above-mentioned extended function is obtained, and the code is loaded together with the basic access mechanism code, and the code is compiled to generate the TDMA protocol code.

(2) Assume that the target MAC protocol is the ALOHA protocol, and the ALOHA protocol is a mechanism for sending as desired. In order to avoid conflicts, the sending probability can be used to control before sending. If you want to generate a time slot ALOHA protocol that sends with probability p and requires a certain reply, the generation process is as follows: According to the content of the ALOHA protocol, it can be seen that in the basic interface In terms of the entry mechanism, the required extended functions include: resource reservation function, listening function, handshake function, backoff function, confirmation function, transmission probability control function and synchronization management function.

By setting the content of the configuration parameters corresponding to the above-mentioned extended functions as preset data (for example: 1) to determine the selection of the above-mentioned extended functions, the user can configure the corresponding configuration parameters as follows:

Resource obligate-flag is set to 0XFF, which means invalid;

CS-flag is set to 0, indicating that ALOHA is used;

Handshake-flag is set to 0, and the handshake mechanism is not used;

CWmin-fix is set to 1, CWmin is set to 0;

ACK-flag is set to 1, valid; ACK-type: set to X02, indicating that the broadcast service needs to be confirmed;

Set p-flag to 0, which means manual fixed configuration is adopted, such as SENDP=0.2;

Synchronization-flag is set to 1, indicating that a synchronous network is used; the synchronization management unit performs modulo M counting on the counting of time slots, for example, initializing M=20.

Perform a logic check on the above parameters, obtain the code for the above-mentioned extended functions, and perform code loading and code compiling together with the basic access mechanism code to generate the ALOHA protocol code.

(3), assuming that the target MAC protocol is: a non-slotted CSMA protocol with a handshake mechanism and a confirmation mechanism, the generation process is as follows:

According to the content of the agreement, in the basic access mechanism, the required extended functions include: resource reservation function, interception function, handshake function, backoff function, confirmation function, transmission probability control function and synchronization management function.

By setting the configuration parameters corresponding to the above-mentioned extended functions to preset data (for example: 1) to determine the selection of the above-mentioned extended functions, the user can configure the corresponding configuration parameters as follows:

Resource obligate-flag is set to 0XFF, which means invalid;

CS-flag is set to 0XFF, invalid;

Handshake-flag is set to 1, valid;

CWmin-fix=0, manually set, such as CWmin=32;

ACK-flag is set to 1, valid;

ACK-type is set to X01, indicating that the unicast service needs to be confirmed;

Set p-flag to 0, SENDP=0;

Setting the Synchronization-flag to 0 indicates that an asynchronous network is used.

Check the logic of the above parameters, obtain the code for the above-mentioned extended functions, load the code together with the basic access mechanism code, and compile the code to generate the non-slotted CSMA protocol code with handshake mechanism and confirmation mechanism.

The above embodiment of the MAC protocol generation method can be applied in a wireless multi-hop network, and supports communication between nodes of different protocols. It is assumed that node A is a source node (ie, a sending node), and node B is a destination node (ie, a receiving node). The protocol run by A is the time slot ALOHA protocol, and the protocol run by node B is the carrier sense protocol of four handshakes.

If node A and node B want to achieve communication, it is necessary: node A converts the protocol to the protocol run by node B, that is, both parties use the carrier sense protocol as the communication protocol; or node B converts the protocol to the protocol run by node A protocol, that is, both parties use the slotted ALOHA protocol as the communication protocol.

Please refer to FIG. 3 , which is a flowchart of Embodiment 1 of a node communication method according to the present invention.

After completing the preprocessing steps in the above-mentioned MAC protocol generation method embodiment, enter the following steps:

Step S301 , Node A learns that the MAC protocol run by Node B is a four-handshake carrier sense protocol.

Step S302, Node A generates a carrier sense protocol for four handshakes.

Node A generates a four-handshake carrier sense protocol according to the MAC protocol generation method described above.

Step S303, Node A and Node B communicate using the carrier sense protocol of the four handshakes as the communication protocol.

The way for node A to know the MAC protocol run by node B can be as follows:

Node A records the protocol version number used by node B through idle listening. This version number describes the access mechanism and message interaction process of node B, as shown in Table 2.

Table 2

local node (node A) Node B Node D Node F V1.1 V2.1 V3.0 V1.1 Custom parameters: Custom parameters: Custom parameters: Custom parameters:

Among them, the user-defined parameters are set by the user and stored in a separate manner. If they are original parameters of the protocol, there is no need to record them.

The version number of the protocol can be stored in a preset address, which can indicate the operating rules of the protocol in the data structure, which is mainly used for the intercommunication and coexistence between different protocols. The arrangement of the protocol version number is described in Table 3 as an example. What is adopted in the embodiment of the invention is that each version number consists of three digits:

The first digit: indicates what the basic access mechanism is, such as TDMA, ALOHA, CSMA;

The second digit: indicates synchronous protocol or asynchronous protocol, such as slotted ALOHA, non-slotted ALOHA;

The third digit: Indicates the selection of each extended function.

table 3

Protocol version number Basic Access Mechanism reserved listening handshake retreat confirm Probability Synchronize V1.1.1 TDMA have none none none none P=0 have

[0185] V1.1.2 TDMA have none none none none P=n have V1.1.3 TDMA have none none none none P initial = n have ... V2.1.1 ALOHA none none none none none none none V2.1.2 ALOHA none none none none have fixed none ... V3.1.1 P persisted CSMA none have none have none have none V3.1.2 P persisted CSMA none have none have have have none ...

It should be noted that if ALOHA is used for sending and CSMA is used for receiving, then only CSMA can be converted to ALOHA. Because ALOHA does not listen, it cannot know the protocol version number of the receiving node. For this situation, the present invention provides another embodiment.

Please refer to FIG. 4 , which is a flowchart of Embodiment 2 of a node communication method according to the present invention.

After completing the preprocessing steps in the above-mentioned MAC protocol generation method embodiment, enter the following steps:

Step S401, Node B learns that the MAC protocol run by Node A is the slotted ALOHA protocol.

Step S402, Node B generates a slotted ALOHA protocol.

Node B generates the slotted ALOHA protocol according to the method for generating the MAC protocol described above.

Step S403, Node A and Node B communicate using the slotted ALOHA protocol as the communication protocol.

The way node B learns the protocol run by node A is the same as the way node A gets the protocol run by node B mentioned above. Through idle listening, it records the protocol version number used by node A. According to the protocol version number Determine the MAC protocol that node A is running.

It should be noted that, in order to accomplish different control functions, it is often necessary to define multiple different packet formats in one protocol. In addition, there are various ways to describe the same control index. For example, NAV (network allocation vector, network allocation vector) can be described by absolute time or epoch. In the present invention, the definition of the general message format must fully consider various control messages and index description fields that may be used in the protocol.

Based on the summary of commonly used message types in the MAC protocol, the embodiment of the present invention pre-establishes a basic message library to meet the needs of users in most cases, and reserves a general extension interface for users to customize.

Fig. 5 shows a schematic diagram of a message format.

in:

Ver-Num: protocol version number: each protocol version number corresponds to a set of parameters in the MIB.

S-ID: source node address.

D-ID: destination node address.

P-Type: frame type.

P-Subtype: subframe type.

NAV: Network Allocation Vector, indicating how long the communication will continue.

SDU-len: length of service data unit.

Ext-len: Extended control field length.

Corresponding to the above-mentioned embodiment of a method for generating a MAC protocol for media access control, the present invention discloses a device for generating media access control.

Please refer to FIG. 6 , which is a schematic structural diagram of an embodiment of an apparatus for generating media access control according to the present invention.

This embodiment includes: a first storage unit 111 , a second storage unit 112 , a first processing unit 113 and a second processing unit 114 .

in:

The first storage unit 111 is used for storing a basic access mechanism identifier and a corresponding code.

The second storage unit 112 is used to store various extended function identifiers and corresponding codes, as well as configurable parameters corresponding to each extended function.

The first processing unit 113 is configured to configure the configurable parameters according to the target MAC protocol and select the extended function identifier corresponding to the configuration parameter whose content is equal to the preset data.

The second processing unit 114 is configured to load and compile the code corresponding to the selected extended function identifier together with the code of the basic access mechanism according to the content of the configurable parameters, to generate the target MAC protocol.

The specific working principles and processes have been described in detail in the foregoing method embodiments, and will not be repeated here.

Aiming at the embodiment of the node communication method described above, the present invention discloses a wireless multi-hop network, which includes several nodes, and the nodes include a medium access control MAC protocol generation device, a MAC protocol determination unit and a communication unit.

The MAC determining unit is used to determine the MAC protocol of the target node before the communication unit communicates with the target node.

The MAC protocol generation device pre-stores the basic access mechanism identification and corresponding codes, various extended function identifications and corresponding codes, and configurable parameters corresponding to each extended function, and the user configures the MAC protocol according to the target node. When the configurable parameters are configured, the extended function identification corresponding to the configuration parameter whose content is equal to the preset data is obtained, and then the code corresponding to the selected extended function identification is matched with the code of the basic access mechanism according to the content of the configurable parameters. Load and compile together to generate the MAC protocol of the target node.

The communication unit sends data to the target node according to the generated MAC protocol, and receives data fed back by the target node.

The composition and working process of the MAC protocol generation device have been described in detail above, and will not be repeated here. The communication process between nodes has also been described in detail in the foregoing part of the node communication method embodiment, and will not be repeated here. Similarly, the process of the MAC protocol determining unit determining the MAC protocol of the node has been described in detail above, and will not be repeated here.

In the embodiment of the present invention, an access mechanism is used as a basic access mechanism, and a preset configurable mechanism is used as an extended part. Select and configure the mechanism of the extension according to the user's needs, and combine it with the basic access mechanism to generate a corresponding protocol. Using the MAC protocol generation method disclosed in the embodiment of the present invention, the corresponding MAC protocol can be generated as required to meet the various needs of users, and realize the intercommunication between different access mechanisms: for example, some nodes in the network use the ALOHA protocol, and other If a part of the nodes adopts the CSMA protocol, the two parts of the nodes can communicate through the solution disclosed in the present invention.

Those of skill in the art would understand that information, messages and signals may be represented using any of a number of different technologies and technologies. For example, the messages and information mentioned in the above description can be expressed as voltage, current, electromagnetic wave, magnetic field or magnetic particles, light field or any combination of the above.

Professionals can further realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software or a combination of the two. In order to clearly illustrate the possible For interchangeability, in the above description, the composition and steps of each example have been generally described according to their functions. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

The steps of the methods or algorithms described in connection with the embodiments disclosed herein may be implemented by hardware, software modules executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other Any other known storage medium.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (12)

1. a medium access control MAC agreement generation method is characterized in that, comprising:

Pre-treatment step:

Determine basic access mechanism;

According to user's request the extended function of multiple configurable mechanism is set, and configurable parameter is set at the extended function of each configurable mechanism;

Generate step:

When the user is configured configurable parameter according to the Destination MAC agreement, determine that content is the extended function of the configurable parameter correspondence of preset data;

The extended function of the configurable mechanism selected carried out with described basic access mechanism code loads, compiling, generate described Destination MAC agreement.

2. the method for claim 1, it is characterized in that, described basic access mechanism is the CSMA agreement that p adheres to, described extended function is: resource reservation function, listening functions, handshake function, back-off function, affirmation function, sending probability controlled function or management by synchronization function.

3. a node communication method is applied to wireless multi-hop network, it is characterized in that, comprising:

Pre-treatment step:

Determine basic access mechanism;

According to user's request the extended function of multiple configurable mechanism is set, and configurable parameter is set at the extended function of each configurable mechanism;

Generate step:

Sending node was determined the MAC agreement of this receiving node before sending data to receiving node, when the user is configured configurable parameter according to this MAC agreement, determine that content equals the extended function of the configurable parameter correspondence of preset data;

Sending node carries out code to the extended function of selecting with described basic access mechanism and loads, compiles, and generates described MAC agreement;

Communication steps:

Described sending node and receiving node communicate described MAC agreement as communication protocol.

4. method as claimed in claim 3 is characterized in that, sending node determines that the concrete mode of the MAC agreement of receiving node is:

Sending node was intercepted by the free time, write down the protocol version information of this receiving node, and this version number information comprises the configurable parameter content of each expanded function correspondence;

Sending node is determined the MAC agreement of receiving node according to described configurable parameter content.

5. as claim 3 or 4 described methods, it is characterized in that, described basic access mechanism is the CSMA agreement that p adheres to, described extended function is: resource reservation function, listening functions, handshake function, back-off function, affirmation function, sending probability controlled function or management by synchronization function.

6. a node communication method is applied to wireless multi-hop network, it is characterized in that, comprising: pre-treatment step:

Determine basic access mechanism;

According to user's request the extended function of multiple configurable mechanism is set, and configurable parameter is set at the extended function of each configurable mechanism;

Generate step:

Receiving node is determined the MAC agreement of sending node, when the user is configured configurable parameter according to this MAC agreement, determines that content equals the extended function of the configurable parameter correspondence of preset data;

Receiving node carries out code to the extended function of selecting with described basic access mechanism and loads, compiles, and generates described MAC agreement;

Communication steps:

Described sending node and receiving node communicate described MAC agreement as communication protocol.

7. method as claimed in claim 6 is characterized in that, receiving node determines that the concrete mode of the MAC agreement of sending node is:

Receiving node was intercepted by the free time, the protocol version information of record sending node, and this version number information comprises the configurable parameter content of each expanded function correspondence;

Receiving node is determined the MAC agreement of sending node according to described configurable parameter content.

8. as claim 6 or 7 described methods, it is characterized in that, described basic access mechanism is the CSMA agreement that p adheres to, described extended function is: resource reservation function, listening functions, handshake function, back-off function, affirmation function, sending probability controlled function or management by synchronization function.

9. a medium access control MAC agreement generating apparatus is characterized in that, comprising:

First memory cell is used to store basic access mechanism sign and respective code;

Second memory cell is used to store the extended function sign and the corresponding code of multiple configurable mechanism, reaches the extended function configuration parameter corresponding with each configurable mechanism;

First processing unit is used for when the user is configured configurable parameter according to the Destination MAC agreement, determines that content equals the extended function sign of the configurable parameter correspondence of preset data;

Second processing unit is used for the code of the corresponding code of the extended function sign of selecting with described basic access mechanism loaded, compiles, and generates described Destination MAC agreement.

10. device as claimed in claim 9, it is characterized in that, basic access mechanism is the CSMA agreement that p adheres to, described extended function is: resource reservation function, listening functions, handshake function, back-off function, affirmation function, sending probability controlled function or management by synchronization function.

11. a wireless multi-hop network comprises some nodes, described node comprises communication unit, it is characterized in that, described node also comprises medium access control MAC agreement generating apparatus and MAC agreement determining unit;

Described MAC determining unit is used for determining the MAC agreement of this destination node that before communication unit and destination node communicate described device comprises:

First memory cell is used to store basic access mechanism sign and respective code;

Second memory cell is used to store the extended function sign and the corresponding code of multiple configurable mechanism, and the configurable parameter corresponding with the extended function of each configurable mechanism;

First processing unit is used for when the user is configured configurable parameter according to the MAC agreement of destination node, determines that content is the extended function sign of the configurable parameter correspondence of preset data;

Second processing unit is used for the code of the corresponding code of the extended function sign of selecting with described basic access mechanism loaded, compiles, and generates the MAC agreement of described destination node;

Described communication unit sends data according to the MAC agreement of described generation to destination node, and receives this destination node feedback data.

12. network as claimed in claim 11, it is characterized in that, basic access mechanism is the CSMA agreement that p adheres to, described extended function is: resource reservation function, listening functions, handshake function, back-off function, affirmation function, sending probability controlled function or management by synchronization function.

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